我在樹梅派 ,作業系統為ubuntu 20.04,docker版本為20.10.2

下載ubuntu images

 docker pull ubuntu
或是
 docker run -ti ubuntu:20.04

查看了有哪些 images,ubuntu 有下載

pi@raspberrypi:~ $ docker images
REPOSITORY              TAG       IMAGE ID       CREATED        SIZE
eric19740521/apache03   latest    498efb6c7a0e   15 hours ago   213MB
ubuntu                  latest    612a7284cf7c   2 weeks ago    49.8MB
portainer/portainer     latest    dbf28ba50432   6 months ago   62.5MB

執行互動模式,docker run -ti ubuntu

date 查詢日期,發覺日期不是最新的

pi@raspberrypi:~ $ docker run -ti ubuntu
root@05a5540256da:/# ls
bin   dev  home  media  opt   root  sbin  sys  usr
boot  etc  lib   mnt    proc  run   srv   tmp  var
root@05a5540256da:/# date
Mon Mar  2 22:42:03 UTC 1970

apt update這個也會出錯

測試底下兩個images,是正常的
docker pull ubuntu:xenial-20210114
docker pull ubuntu:xenial

pi@raspberrypi:~ $ docker pull ubuntu:xenial
xenial: Pulling from library/ubuntu
2af2a813aac2: Already exists
470ef2a276bd: Already exists
b01c8ce931ce: Already exists
3b9ba02aed01: Already exists
Digest: sha256:e74994b7a9ec8e2129cfc6a871f3236940006ed31091de355578492ed140a39c
Status: Downloaded newer image for ubuntu:xenial
docker.io/library/ubuntu:xenial
pi@raspberrypi:~ $
pi@raspberrypi:~ $ docker images
REPOSITORY              TAG       IMAGE ID       CREATED        SIZE
eric19740521/apache03   latest    498efb6c7a0e   15 hours ago   213MB
ubuntu                  xenial    94880fe21137   2 weeks ago    104MB
ubuntu                  20.04     612a7284cf7c   2 weeks ago    49.8MB
ubuntu                  latest    612a7284cf7c   2 weeks ago    49.8MB
portainer/portainer     latest    dbf28ba50432   6 months ago   62.5MB
pi@raspberrypi:~ $ docker run -ti ubuntu:xenial
root@943d4c854157:/# date
Thu Feb  4 03:16:26 UTC 2021
root@943d4c854157:/#